Do Septic Tank Lids Need To Be Covered with A Form of Insulation ??

[NorPlan2]

I just recently had my Septic Tank drained and prior to the Pump Trucks arrival I had cleared away 6 / 8" of Top Soil exposing the Lids.. Since no grass grew around the Septic Tank I had built a Deck Platform over the tank as well... Question, I'm thinking of removing the Deck Platform altogether as I'm told I don't need the 6 / 8" of Top Soil on top as the Septic Tank as it is active , doesn't sit idle .. We live in Eastern Ontario so our Winter Temps can dip pretty low even with the Windchill Factor.. Is that True (??) Also I'm looking at those Plastic Sleeve Kits with the Plastic Lids , Question, there'd be no problem with the Cement Lid removed ?? Thoughts & Opinions Appreciated, Cheers Thanks

 

[FishScreener]

i would install the plastic riser and lid, but make a foam plug to fit the inside of the riser.